The Truth About Grass-Fed Beef

Grass-fed cows almost always have less total fat in their meat than corn-fed cows.

What's old is new again. Across the U.S. farmers are turning back to a traditional method of cattle raising: feeding cows on grassy pastures instead of troughs filled with corn. A decade ago, there were only about 50 grass-fed-cattle operations left in the United States. Now, there are thousands and the numbers are growing.

Just look to your local farmer's market or specialty grocer for the evidence. It's much easier these days to get your hands on grass-fed beef from farms where cows spend their days out on pasture grazing on all sorts of grasses — from clover to wild onions to different types of tufted grasses called fescue. And beef eaters notice a difference from corn-fed cattle. (Watch my Tiny Desk Kitchen video above with NPR's Susan Stamberg and Ari Shapiro to see which beef they preferred.)

Tiny Desk Kitchen host Allison Aubrey (left) gave a blind taste test of grass-fed beef and corn-fed beef to NPR's Ari Shapiro and Susan Stamberg. See the video for the results. (NPR)

The Taste

So there's more of this meat on the market, but is it really any different? I was curious about differences — both in taste and nutrition — so I called on farmer Forrest Pritchard, who runs Smithfield Farm in Berryville, Va.

"I think of my cows as four-legged lawn mowers," Pritchard told me as we walked his pastures one morning. After he pointed this out, I noticed that his cows were always on the move. That exercise leads to more muscle tone. And the resulting beef? Well it can taste a little chewier than most folks are accustomed to. Taste testers say the flavor is more varied than the typical grocery store cuts of beef that come from corn-raised cows.

From Pasture To Trough

Farmers first made the switch from grass to corn years ago because corn allows them to fatten up their cattle faster.

Cows love to eat clover, which is rich in omega-3 fatty acids. Eating clover and other grasses gets those heart healthy fats into their meat.

It's the difference, for humans, between eating bags of spinach all day vs. dense, calorie-rich oatmeal. A lot of corn-fed-cattle raisers still start their animals out on pasture, but then quickly move them to troughs of grain for fattening.

That means farmers can raise more cattle and in smaller spaces — because they don't need all of that pasture. And yes, that means there's more beef for the millions and millions of hungry Americans.

Something Fishy

All right, there is a difference in taste, for sure. But what I'm really interested in is whether it's nutritionally any different. And the story gets a little fishy here. You know how nutritionists are always recommending fish? Well, that's because many fish are rich in heart-healthy omega-3 fatty acids.

And where do the fish get these omega-3s? They eat it. (Well, generally, the tiniest sea creatures eat algae, and it moves up the food chain to bigger fish.) With grass-fed cows, it's a similar story. Omega-3s are in their meat-- because they're eating grasses and clover rich in these heart-healthy fatty acids.

Still, with 35 milligrams of heart-healthy fats per serving, grass-fed steak can't compete with a salmon dinner, which has about 1,100 milligrams. But it's a significant difference in omega-3s between grass-fed and corn-fed beef. (You can calculate the fat/protein or micronutrients of any food in your diet with this USDA tool.)

And since grass-fed cattle are typically leaner, almost all cuts of grass-fed beef have less total fat than beef from corn-raised cattle. Of course, the breed of cattle leads to variation, too.

The Cost

There's a lot of variation in price on both sides of the aisle — and grass-fed will usually cost more. Farmers have to pay for all that pasture. A random price check found Whole Foods selling a pound of grass-fed sirloin for $9.99; Safeway was selling its corn-fed sirloin for $7.99 a pound. (On the day we checked, Safeway had the sirloin on sale for $5.99 a pound.)

My conclusion? On the whole, grass-fed beef is better for you than corn-fed. But it may not give you that melt-in-your-mouth sensation you grew up on, and it's going to cost you a more. So are these differences worth the price? That's up to you.